change sparse_update to adam_update

paddle/fluid/operators/optimizers/adam_op.h

@@ -202,7 +202,7 @@ struct SparseAdamFunctor {
         row_count_(row_count),
         sparse_mode_(sparse_mode) {}
 
-  inline HOSTDEVICE void sparse_update(size_t i, T g) const {
+  inline HOSTDEVICE void adam_update(size_t i, T g) const {
     // The following code is the same as dense
     T mom1 = moment1_[i];
     T mom2 = moment2_[i];
@@ -228,7 +228,7 @@ struct SparseAdamFunctor {
     auto row_idx =
         math::BinarySearch<int64_t>(rows_, row_count_, i / row_numel_);
     T g = row_idx >= 0 ? grad_[row_idx * row_numel_ + i % row_numel_] : 0;
-    sparse_update(i, g);
+    adam_update(i, g);
   }
 };
 
@@ -364,7 +364,7 @@ class AdamOpKernel : public framework::OpKernel<T> {
           for (size_t offset = 0; offset < row_numel; ++offset) {
             size_t i = rows[row_index] * row_numel + offset;
             T g = grad_data[row_index * row_numel + offset];
-            functor.sparse_update(i, g);
+            functor.adam_update(i, g);
           }
         }
       } else {